Buildbot status page: https://uberchromegw.corp.google.com/i/chromium.perf/builders/Android%20Galaxy%20S5%20Perf%20%281%29?numbuilds=200

Example STDIO: https://uberchromegw.corp.google.com/i/chromium.perf/builders/Android%20Galaxy%20S5%20Perf%20%281%29/builds/4074/steps/blink_style.key_mobile_sites/logs/stdio

CRITICAL:root:STDERR: [0919/075859:ERROR:host_forwarder_main.cc(392)] ERROR: Connection to device failed.ERROR: Existing controllers:

INFO:root:Killing device_forwarder.
INFO:root:[host]> /b/rr/tmp6E8w6b/w/src/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 3208e0600bb251f3 shell '( test -e /data/local/tmp/forwarder/device_forwarder );echo %$?'
INFO:root:[host]> /b/rr/tmp6E8w6b/w/src/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 3208e0600bb251f3 shell '( LD_LIBRARY_PATH=/data/local/tmp/forwarder/  /data/local/tmp/forwarder/device_forwarder --kill-server );echo %$?'
INFO:root:[host]> /b/rr/tmp6E8w6b/w/src/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 3208e0600bb251f3 shell '( ps );echo %$?'
INFO:root:Currently running device_forwarders:
WARNING:root:Failed to create forwarder. Currently forwarded connections:
INFO:root:[host]> /b/rr/tmp6E8w6b/w/src/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 3208e0600bb251f3 forward --list
WARNING:root:  
WARNING:root:Device tcp sockets in use:
INFO:root:[host]> /b/rr/tmp6E8w6b/w/src/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 3208e0600bb251f3 pull /proc/net/tcp /tmp/tmplfMmed/tmp_ReadFileWithPull
WARNING:root:    sl  local_address rem_address   st tx_queue rx_queue tr tm->when retrnsmt   uid  timeout inode                                                     
WARNING:root:     0: 0100007F:13AD 00000000:0000 0A 00000000:00000000 00:00000000 00000000     0        0 7647 1 00000000 100 0 0 10 0                              
WARNING:root:Alive webpagereplay instances:
INFO:root:Try printing formatted exception: None None None

Traceback (most recent call last):
  RunBenchmark at /b/rr/tmp6E8w6b/w/src/third_party/catapult/telemetry/telemetry/internal/story_runner.py:327
    benchmark.ShouldTearDownStateAfterEachStorySetRun())
  Run at /b/rr/tmp6E8w6b/w/src/third_party/catapult/telemetry/telemetry/internal/story_runner.py:222
    test, finder_options.Copy(), story_set)
  traced_function at /b/rr/tmp6E8w6b/w/src/third_party/catapult/common/py_trace_event/py_trace_event/trace_event_impl/decorators.py:52
    return func(*args, **kwargs)
  __init__ at /b/rr/tmp6E8w6b/w/src/third_party/catapult/telemetry/telemetry/page/shared_page_state.py:98
    self.platform.network_controller.InitializeIfNeeded()
  traced_function at /b/rr/tmp6E8w6b/w/src/third_party/catapult/common/py_trace_event/py_trace_event/trace_event_impl/decorators.py:52
    return func(*args, **kwargs)
  InitializeIfNeeded at /b/rr/tmp6E8w6b/w/src/third_party/catapult/telemetry/telemetry/core/network_controller.py:21
    self._network_controller_backend.InitializeIfNeeded()
  InitializeIfNeeded at /b/rr/tmp6E8w6b/w/src/third_party/catapult/telemetry/telemetry/internal/platform/network_controller_backend.py:59
    self._platform_backend.GetPortPairForForwarding(local_port))
  Create at /b/rr/tmp6E8w6b/w/src/third_party/catapult/telemetry/telemetry/internal/forwarders/android_forwarder.py:25
    return AndroidForwarder(self._device, port_pair)
  __init__ at /b/rr/tmp6E8w6b/w/src/third_party/catapult/telemetry/telemetry/internal/forwarders/android_forwarder.py:60
    [(port_pair.remote_port, port_pair.local_port)], self._device)
  Map at /b/rr/tmp6E8w6b/w/src/third_party/catapult/devil/devil/android/forwarder.py:117
    exit_code, '\n'.join(output)))
HostForwarderError: /b/rr/tmp6E8w6b/w/src/third_party/catapult/devil/bin/deps/linux2/x86_64/forwarder_host exited with 1:

The earliest I see this happening is during this (https://uberchromegw.corp.google.com/i/chromium.perf/builders/Android%20Galaxy%20S5%20Perf%20%281%29/builds/4001) run on 9/7.